Please let us know the outcome. As a teenager I don’t think I ever told my dad an outright lie, in fact I doubt I ever dipped below 90% truthfulness. However, with a little imagination I could do wonders with that 10% allowance. The clues, as you have reported them tend to point to water in the engine. Although with the standard filter and air box in place, it would take the front of the car being submerged to the bottom of headlights for this to happen.
A popular modification is a cold air intake; some of them locate the intake filter down low at the bottom of the car. These are not meant for roads with any standing water in puddles etc. Hopefully that is not the case here.